Error in Activating Windows XP machine.

I want to activate my Windows XP machine, so I go to Start menu and Click on "Activate Windows" but instead I got this error message.
"Activate Windows cannot run because local scripting has been disabled on this computer. Scripting may have been disabled for virus prevention or as a security measure. Once local scripting has been enabled, run Activate Windows again."
I ask from my friend and he told me to activate it by typing this " oobe/msoobe/a " (without the double quotation) from the Start Menu dialog but I get the same error.
